Propane VS N-Butane extraction


#42

Someone else said it, but I was recovering all the solvent because I couldn’t get a low enough temp on my collection vessel because I wasn’t allowed to do a dryice slurry. I kinda stepped back because they were doing warm runs and expecting sellable results and i dont have those skills.

I made a 65/35 propane butane mix and also ran it through our dewaxer and was able to crystallize that in our diamond miner, 110 g puck of crystal and 110 of terps, crystals tested at 99.5%THCA. I have a second run about to finish up so I will see how it did. It was the same live material and solvent, but the was a change in the crystallization process so idk how its going to turn out.


#43

Correct, as you go up in size for any given model of clamp, the pressure rating will go down. Once you get up to 12" diameter, the service pressure rating will be greatly diminished. Even the incredibly heavy triple-bolted ASME clamps do not really have high enough pressure rating at the 12" size.

The engineering company which certified our extractors for use in a legal processing facility told us that they require 350PSI for any extractor that will touch propane.


#44

Does anyone know if using a blended solvent for a long time results in the blend changing?
Say your running a 70/30 butane/propane blend, you fill a 100lb solvent tank and use it for say 30 runs @ 24lbs of solvent per run, Every time you recover, you take .5lbs of solvent out with your pour. If propane evaps quicker than butane, will the .5lbs of solvent poured out with each run be mostly butane? And will your ration eventually go from 70/30 to 60/40 and so on?


#45

Most would tell u yes…however I’m not calling him out but boss man here once told my inside that vessel it doesn’t quiet work like that…

But I would think yes


#46

Thank you for asking that. I was curious about the same thing. I was actually concerned about if 99.9998% butane would turn to a lower percentage or if the percentage of solvent would be lowered


#47

Id love to hear the real scientific explanation of this because you can think of it 2 ways which probably what confuses most of us…Lets take 70/30 for example.

One way to think is these are 2 separate gases with 2 pretty different boiling points. Distillation would teach us the lower boiling point is going come over first(propane)…then the high(butane). Thus the ratio changing.

Another way to look at it is the mixed solvent are mixed now and have a whole new different boiling point which is one number. This would make me think the ratio is the same from first drop to last drop.

Im leaning toward the first way. I think the boiling points for these gases are different enough to distill one from another. Thats just my opinion. Lets keep this rolling…We need @QGA to answer this properly. Or someone with a real chemistry degree…I know i dont.


#48

I’m with you 100% on that.
I am at the end of a 100lb tank and I believe I am needing an extra 10psi of nitro to fill my material columns now, and I think it’s due to the higher propane amount in the blend.


#49

I would stand to reason that you can manipulate what’s recovered by being selective in the temp of your recovery vessel like we do when distill the nasties out of the tane


#50

You’ll lose the butane first and have more propane in the system. The propane will boil off first and get recovered. Then the butane will be left. And you will lose butane each run when you pour off


#51

You seem pretty confident in this answer. You have some experience with it?


#52

no I have never experienced this


#53

What is the question exactly i can try my best:D


#54

Basically the question now is, what is the azeotrope of butane and propane?


#55

Propane boils off at -42°C, butane boils off at, roughly, 0c. They boil off separately. First the propane, then the butane.


#56

Dred i was told that this is true, until it reaches an azeotrope. Which means it shares the same boiling point.


#57

Inisde collection pot, sealed…does a blended solvent blended to make single boiling point at some point…

Or does the mix boil at the 2 specific separate boiling point no matter the conditions


#58

Azeotrope-
a mixture of two liquids which has a constant boiling point and composition throughout distillation.


#59

I know what it means.

But I don’t think it happens as much as you are thinking.


#60

I mean, to an extent. Because straight propane is a lot higher than what the mixture presents. I’m not saying that it doesn’t happen, but they separate.

But

The propane boils off first. That’s why it’s fast in the beginning with high pressure and magically, right around halfway or under, it slows down. Because most of the propane is gone, and you’re left with slow ass butane.


#61

Dred I really only think you are half right on this. You are 100% correct that the propane will evaporate first, but NOT once it’s in azeotrope. Once that happens, They share a common boiling point and evaporate simultaneously. As far as I understand anyways.

If we can find the azeotrope for butane & propane. That would allow us to make sure they evap at the exact same temp. Meaning you wouldn’t be “left with slow ass butane”, you’d speed up the butane evap rate while lowering the propane evap rate. Right?